This invention relates generally to gas turbine engines, and more specifically to gas turbine engine assemblies and methods of assembling the same.
At least some known gas turbine engines include a fan assembly, a core engine, and a low-pressure or power turbine. The core engine includes at least one compressor, a combustor, and a high-pressure turbine that are coupled together in a serial flow relationship. Air entering the core engine is mixed with fuel and ignited to form a high energy gas stream. The high energy gas stream flows through the high-pressure turbine to rotatably drive the high-pressure turbine and thus the compressor via a first drive shaft. The gas stream further expands through the low-pressure turbine, which rotatably drives the fan assembly through a second drive shaft.
To improve engine efficiency, it is desirable to operate the fan assembly at a relatively lower speed than the operating speed of the high-pressure turbine. However, operating the fan at a relatively slow speed may be detrimental to the operation of a booster compressor. As such, additional booster stages may be required in order to produce the desired overall pressure ratio, thus increasing the overall cost, design complexity, and weight of the gas turbine engine.